Re: [PATCH 1/2] mm: move filemap_range_needs_writeback() into header

[Jens Axboe <axboe@kernel.dk>]

On 12/3/21 9:16 AM, Matthew Wilcox wrote:
> On Fri, Dec 03, 2021 at 08:38:28AM -0700, Jens Axboe wrote:
>> +++ b/include/linux/fs.h
> 
> fs.h is the wrong place for these functions; they're pagecache
> functionality, so they should be in pagemap.h.
> 
>> +/* Returns true if writeback might be needed or already in progress. */
>> +static inline bool mapping_needs_writeback(struct address_space *mapping)
>> +{
>> +	return mapping->nrpages;
>> +}
> 
> I don't like this function -- mapping_needs_writeback says to me that it
> tests a flag in mapping->flags.  Plus, it does exactly the same thing as
> !mapping_empty(), so perhaps ...
> 
>> +static inline bool filemap_range_needs_writeback(struct address_space *mapping,
>> +						 loff_t start_byte,
>> +						 loff_t end_byte)
>> +{
>> +	if (!mapping_needs_writeback(mapping))
>> +		return false;
> 
> just make this
> 	if (mapping_empty(mapping))
> 		return false;
> 
> Other than that, no objections to making this static inline.

Good idea, I'll make that change.

-- 
Jens Axboe